store value in eeprom before starting

Your question is rather confusing, but you can initialize the internal data EEPROM in a PIC in the source code. For an external EEPROM you can add code to the startup routine that loads default values to the EEPROM the first time it runs.

Settings stored in EEPROM, would they be permanent? If so they could be eventually writen at programming time.

If settings change eventually, prior starting, give the option to do so or to bypass the parameter inputting process and move to the operation.

mah said:

I have lcd connected to microcontroller, and i want to sore numbers using external push buttons, but i want to store values before entering the processing mode. for instance microcontroller is off then i want to push a button to enter (X mode) to adjust parameters then exit this mode and restart to enter the operation mode( like enter configuration mode of devices while they are turned off). How to do this?​

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It is difficult to understand exactly what you are trying to do, but I think that a reasonable approach would be to program the microcontroller for both "parameter adjustment" and "operation". That is, when starting, the program, read your input, adjust parameters, and subsequently enter operation mode. You could even have the program examine the position of a switch upon starting to determine if it needs to go into adjustment mode first.

That approach is pretty straight forward and I am wondering if you considered it but rejected it for some reason. IOW, why cant you have your code do both?